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Friday, 02 October 2026
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Chemistry Past Questions and Answers

Topic: Painting as ways of preventing iron from corrosion.

Jamb Chemistry Questions - Painting as ways of preventing iron from corrosion.

Question 1:
For iron to rust, there should be present?
  • A Oxygen
  • B Moisture
  • C Carbondioxide
  • D Oxygen and moisture
  • E Oxygen, moisture and carbondioxide
View Answer & Explanation
Question 2:
If a current of 1.5 A is passed for 4.00 hours through a molten tin salt and 13.3g of tin is deposited, what is the oxidation state of the metal in the salt?
(Sn = 118.7, F = 96500 C mol-1)
  • A 1
  • B 2
  • C 3
  • D 4
View Answer & Explanation
Question 3:
The removal of rust from iron by treatment with tetraoxosulphate (IV) acid is based on the?
  • A Hydrolysis of the iron
  • B Reaction of acid with base
  • C Oxidationof the rust
  • D Dehydration of the iron
View Answer & Explanation
Question 4:
The reddish-brown rust on iron roofing sheets consists of
  • A Fe<sup style='font-size: smaller;'>3+</sup>(H<sub style='font-size: smaller;'>2</sub>O)<sub style='font-size: smaller;'>6</sub>
  • B FeO.H<sub style='font-size: smaller;'>2</sub>O
  • C Fe<sub style='font-size: smaller;'>2</sub>O<sub style='font-size: smaller;'>3</sub>.3H<sub style='font-size: smaller;'>2</sub>O
  • D Fe<sub style='font-size: smaller;'>3</sub>O<sub style='font-size: smaller;'>4</sub>.2H<sub style='font-size: smaller;'>2</sub>O
View Answer & Explanation
Question 5:
The haloalkanes used in dry-cleaning industries are
  • A Trichloromethane and tetrachloromethane
  • B Chloroethene and dichloroethene
  • C Trichloroethene and tetrachloroethene
  • D Chloroethane and dichloroethene
View Answer & Explanation